The present invention concerns a cistern structure intended to be used as a subterranean cistern and of which the shell has been formed of a material impermeable to the material to be stored therein.
Steel-lined subterranean oil cisterns have heretofore been built in the manner that the space between the sheet steel shell of the cistern and the rock has been completely filled with concrete by pouring. The thickness of the concrete layer has then varied in the range from 0.1 to 2 meters, depending on the accuracy with which the rock blasting has been done. The drawback encumbering such cisterns is, above all, that in the construction job immense quantities of concrete are required, with the result that the constructing of the cistern is extremely costly. From the detrimental heat generation of the concrete arises the drawback that the steel wall tends to become wavy, for which reason one is generally compelled to use a relatively thick steel wall and bolting with very close spacing. The massive concrete envelope precludes the use of the cistern as storage for cold liquids because the steel shell tends to become detached from the concrete shell. In high cisterns, the ground water pressure causes detrimental stresses acting on the structure, in spite of the draining that is applied. This mode of construction of prior art is also time-consuming, with the result that the total cost of the cistern will be high. The use of poured concrete is advocated by the fact that the corrosion phenomenon occuring in a thick steel shell can be managed by the aid of concrete pouring.